Question

How many calories are in one S.I unit of heat energy?

Answer 1

The SI unit of heat energy is the joule (J).

Since $$1 \text{ cal} = 4.186 \text{ J} \approx 4.2 \text{ J}$$, $$1 \text{ J} = \frac{1}{4.186} \text{ cal} \approx 0.24 \text{ cal}$$.

Therefore, one SI unit of heat energy contains about 0.24 calories.